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Re: Ethan and MahlerFreak

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Ethan Winer

In Reply to: Re: Ethan and MahlerFreak posted by MahlerFreak on March 9, 2007 at 16:00:33:

Excellent post.

Follow Ups:

Re: Ethan and MahlerFreak - David Aiken 22:17:51 03/10/07 (19)
Let me try to restate my concerns one final time so that everyone reading this understands what we are all saying. Please feel free to correct me if I have misstated either of your positions but I don't think I have.
We all agree that the plots show a very even attenuation of sound levels across the displayed frequency range. We all agree that is a suspicious result.
You and Mahlerfreak say that such a result can not be achieved by absorption with panels of the size of these products. I agree.
The manufacturers say they aren't using absorption as the method of achieving the result. Their explanation of the technique they are using is neither detailed nor helpful in understanding what they are doing. That makes it extremely difficult to accept their explanation, which is another reason all 3 of us are suspicious.
None of the above agreed points PROVES the results are bogus. They most definitely give rise to concern but they aren't a proof that something is bogus. If you like you could regard it as circumstantial evidence that the results are bogus but that's as far as it goes. It is not direct evidence of poor testing setup and/or techniques, falsification, trickery, or something worse.
What you have both demonstrated factually, and what I never disagreed with, was that such results can not be obtained by absorption. That does not prove that they cannot be obtained by other means. You both are happy to state that you don't know of any other method to produce such effects and I accept that. I don't know of any other method either. That doesn't prove there isn't one. A proof that the results can't be achieved by absorption does not prove the products don't work by some other method and not knowing of any other method doesn't prove there isn't one. New techniques are discovered every now and then. We have no reasons on the information available to believe that these people have actually come up with a new method but we also have no evidence available to prove they haven't. The lack of information cuts both ways here. It doesn't give us any reason to believe them, but it also doesn't give us the evidence required to say with certainty that they haven't discovered another method. If you can find a bookmaker to take bets on whether or not they have, all 3 of us will be betting the same way but we don't have proof that we're right. We also wouldn't expect to lose the bet. On the information to hand, betting that there isn't a new technique involved has to be regarded as a 'safe bet', even a 'very safe bet', but it isn't up to the standard of proof.
If you want to restate all of the agreed things above and and proceed from there to a conclusion which states that you BELIEVE the results to be bogus I will accept your statement 100% and not argue one bit. That's where I stand with the proviso that I would prefer to say that I believe the results are incorrect. "Bogus" does carry an implication of fraud and it's possible that the manufacturers are sincere but mistaken. I'd prefer some hard evidence of deceit before I chose to use the word 'bogus' but that's my preference and others can choose to be less cautious given that the case for believing that the things don't work is very strong, If you want to take the very major step logically to instead claim that you have proved that the results are bogus, I must disagree. The evidence offered does not prove that. What it does, and what I have said all along, is that it gives very strong reasons (and I mean that in the strongest terms) for doubting the results.
You ask them to prove their results, and that's a valid request, and you also expect that their proof will have to measure up to reasonable scientific standards of proof. That's fine. But what I'm saying is that you should meet similar standards in your statements and one of the things that scientifically acceptable proof rests upon is logically valid arguments when inferences are drawn. Your jump from the evidence cited to your claim of proof that the results are bogus is not logically valid. I don't believe the evidence as it stands allows that jump. I think evidence of a different sort is required for that sort of conclusion, and that evidence would be things like failure to replicate the results and/or an account of their test method, the errors/mistakes made during their tests, and an account of how those errors/mistakes led to the results they claimed.
None of the three of us would not go out and buy the products on the evidence provided. None of us would recommend that anyone else went out and buy them. Where we differ, and the only place where we really differ, is that I hold back from claiming that the results are bogus because I don't believe we have evidence that proves that. What I think we have is evidence which very strongly suggests that the results shown are not accurate.
That is the point I keep trying to make. I'm not trying to deny your evidence. I'm simply trying to point out that it is not sufficient for a claim to have "PROVEN" the results are "bogus" if we're going to rely on scientific standards of proof. It may well be enough to convince readers if the standard of "proof" is one of a lack of reasonable doubt, but that's not the standard applied in science. I definitely believe that there's enough evidence for a reasonable doubt that they work. That doesn't amount to proof that they don't work.
David Aiken
- Re: Ethan and MahlerFreak - Ethan Winer 14:37:38 03/11/07 (1)
  David,
  MF is doing a great job - who was that masked man? - so there's not too much more I can add. But I'll try. :-> )
  > We all agree that the plots show a very even attenuation of sound levels across the displayed frequency range ... You and Mahlerfreak say that such a result can not be achieved by absorption with panels of the size of these products. I agree. <
  I further argue that the only way to get results like that is to lower the volume knob. Nothing you can put into a room will have that effect. If you demolished the building so all the walls fell outward and the speakers were left standing in an empty lot, you still wouldn't get After results like that.
  > What you have both demonstrated factually, and what I never disagreed with, was that such results can not be obtained by absorption. That does not prove that they cannot be obtained by other means. <
  There is no way to get those results other than turning down the volume. Or maybe doing a PhotoShop job on the screen cap.
  > If you want to restate all of the agreed things above <
  I have restated enough times, so let's take a new approach:
  Since we all agree that the results in their After graph are identical to turning down the volume, why does anybody need to buy those panels at all? Just turn down the volume. Then all those nasty room modes and peaks and ringing will be pushed below the noise floor where they won't irritate us critical listeners anymore!
  > You ask them to prove their results, and that's a valid request <
  Has anyone noticed that it's still only the three of us discussing this? If a thread like this were going on about my products, and I knew about it, you can be sure I'd be all over it explaining my position as best I could.
  --Ethan
  - See the hypothetical scenario in my response to MahlerFreak. How would you answer the questions posed? NT - David Aiken 17:39:30 03/11/07 (0)
- Re: Ethan and MahlerFreak - MahlerFreak 11:46:14 03/11/07 (16)
  If anyone reading this doubts the dangers and inefficiencies created by scientific and mathematical illiteracy, this discussion should go a long way toward convincing you. Although, to be fair, inefficiencies almost always create perverse opportunities as well, without which such lucrative industries as high end speaker cable manufacturing and magical room treatment devices would greatly suffer.
  There are so many flaws in David's post that it's difficult to know where to begin, but I'll simply point out that:
  1. The "inference" made from the calculations I performed in my previous post is that the devices in question would have to violate conservation of energy - dramatically - in order to create the measured differences. Since David has already agreed that conservation of energy is a reasonable assumption to make, it is his argument that that draws logically invalid inferences - namely, that there is some principle of operation other than "absorption" which would allow the devices to violate conservation of energy. To be fair, it is possible that David does not recognize that inference, due to the more serious logical flaw of arguing from incomprehension of the subject at hand. Unless you can refute my very simple calculations and modeling assumptions, there is no room for "reasonable doubt" about the validity of these measurements - they are not the result of the devices as described being used as described in a realistic listening room (and note with care the contingencies in that statement, lest David come back and insist that you might create these measurements by using the devices as earmuffs, or attaching them directly to the woofers of your loudspeakers, or stuffing your head into a box constructed of these devices, or some similar bit of face-saving nonsense).
  2. I never used the word "bogus" to describe the measurements. I will leave it to the reader to speculate as to the origins of these measurements, as there are many possible explanations which do not violate the laws of physics, almost all of them having to do with, umm, human factors.
  Beyond this, I am bothered that my previous post describes the issue of room non-linearity in a somewhat awkward and potentially misleading way, and manages to miss an important point at that. The point becomes clearer, hopefully, by concrete example.
  For simplicity, assume we have a listening room 10 feet long, constructed with very rigid walls. For the sake of this example, the other dimensions can be ignored. This 10 foot long room will have "room modes" related to the 10 foot length, room modes being patterns of cancellation and reinforcement in sound frequencies related to the 10 foot length. In this case, we will have room modes at multiples of the frequency 56.5 hertz. For instance, there will be a room mode at 113 Hertz. If we have our speakers play a 113 hertz tone at an average sound level of 100 DB, and begin measuring the sound level at various points in the room, we will discover some interesting things. For instance, at the front and back walls, the sound will actually measure louder than 100 DB. Aha! Here is proof that all of that conservation of energy stuff is BS! How can the sound be louder?! Well, because at other points in the room, it is quieter. For instance, if we measure the sound at a listening location 2.5 feet from the back wall, we will discover that the sound level is way below 100 DB. In fact, if we measure the sound at frequencies in the neighborhood of 113 hertz at that listening location, we will find that there is a sharp dip in the frequency response graph, centered at 113 hertz. This sharp dip occurs because sound reflecting from the back wall is canceled by sound of opposite polarity reflecting from the front wall, at that location, at that frequency.
  Now let's introduce some sound treatment devices on our front and back walls. If these are passive devices, with no power source of their own, conservation of energy says that these devices can't create or destroy the sound energy, only transform it in some way. Part of that transformation might be from sound energy to heat, part of that transformation may be reflection of sound, some of it may be conversion into dynamic magnetic fields which interfere with the skin effect in your $12,000 speaker cables (don't worry, that last is mostly a joke, until it appears in someone's marketing brochure).
  Let's assume for the sake of this example that the sound treatment devices in question are well designed passive absorbers covering much of the back and front walls, capable of absorbing most of the sound energy impinging on their front surfaces at 113 hz. Now we do some measurements again. We find that, intuitively enough, the sound level at 113 hz is significantly reduced near the back wall. Not so intuitively, as we measure the frequency response in the neighborhood of 113 hz at the listening position, we find that the dip in the frequency response graph is not as deep or sharp as before.
  Why? Because our sound treatment devices have now negated much of the sound waves that reflect from the back and front wall and interfere with each other at the listening position, partially removing the non-linearity caused by the cancellation of those two waves. Although our devices absorb energy at non-modal frequencies as well, they do not absorb as much, because the sound at the boundaries is not as loud at non-modal frequencies. The serendipitous result is that a non-linearity at the front and back walls is aiding us in canceling an opposite non-linearity at the listening position, exactly what we want if more uniform frequency response is the goal.
  This leads to an even more non-intuitive conclusion, easily verified with active sound cancellation devices. In order for our sound treatment devices to lower the relative 113 hz level at the listening position, they would have have to amplify the 113 hz level at the front and back walls! Passive, non-powered devices can't amplify, of course. They could be designed and physically constructed to be ineffective absorbing frequencies in a narrow band around 113 hz, thus "amplifying" 113 hz in a relative sense - but that would obviously require a priori knowledge of the room into which they were placed, and of course would be counterproductive if removing room effects is the desired goal.
  What can we learn from all of this? First, every room will have non-linearities due to reflections from the room boundaries, regardless of the dimensions or shape of the room. Second, placement of devices so as to take advantage of room non-linearities is crucial - fortunately, almost all two and three wall corners work well in practice. Third, any boundary reflection energy not absorbed, or canceled by energy from powered, active devices, will continue to create some non-linearities. And finally, to the point of my previous post, it is not possible to introduce generic, passive devices into a room and achieve uniform reduction in sound energy across the frequency spectrum - not that this is desirable for accurate sound reproduction in any case.
  - Re: Ethan and MahlerFreak - David Aiken 15:24:22 03/11/07 (15)
    Re your point 1-
    The reason I said "inference" is because there is no direct evidence that the results are not genuine. The route to that determination is via reasoning rather than physical demonstration.
    You said, and I agreed, that the law of energy conservation could not be broken but you then went on to hold up the open window as an example of the perfect absorber. As I pointed out, it is possible to obtain somewhat better absorption than 1 Sabin per square foot of device under some circumstances, including restricted bandwidth, from a passive device and without violating the Law of Conservation of Energy. We cannot say that there is no possible way of producing this kind of effect because we can never guarantee with 100% certainty that there isn't a way of passively producing the result. We may be pretty damn certain, even 99.99999999999999999999% certain or even a little bit more than that, but we cannot say with total accuracy what techniques will or won't be developed in the future.
    All I'm saying is that without direct evidence showing that the results were not genuinely obtained, there is a logical step involved in the move from the evidence of the plots to the conclusion that they are wrong. That step is inferential.
    Your point 2: Ethan used the word 'bogus'.
    
    Let's set up a different scenario as a hypothetical and ask some questions.
    The scenario: It is some months BEFORE Manfred Schroeder publishes the results of his experiments on generating acoustic diffusion using diffraction gratings. These results lead to the eventual development of diffusors based on mathematical models. At the time we are talking about, some months before publication, the only methods of diffusion in use involve curved surfaces like polycyndrical reflectors.
    Hypothetical question 1: Somebody tells you it is possible to produce more effective diffusion than is currently achievable by using an array of staggered well depths. Do you believe them or do you say it can't be done because there is no known method or theory which indicates that this is possible? Remember, there is at this point in time no published material on this technique from any source.
    Hypothetical question 2: It is now some months later and you have just come across Schroeder's claims but Schroeder is not a researcher at respectable institutions. Instead he is the principal of a small company selling acoustic treatments and the claims are contained in advertisements for a new product, a quadratic residue diffusor. Photos of the device with claims of its effectiveness are contained in the advertisement but no scientific account is given. No scientific account of the device has yet appeared in the professional scientific literature. Do you believe the claims of the advertisement or do you respond in a similar way to the way you would respond to hypothetical question 1 above.
    Hypothetical question 3: The events described in question 2 have not occurred. Instead what has happened is what happened historically. Schroeder is a scientific researcher working at respectable institutions and he publishes his study and theories in the professional scientific manner and you read them in a peer- reviewed scientific journal or hear them in a presentation at a scientific conference on acoustics. A full theoretical and mathematical explanation/description is given along with detailed test description to enable others to repeat the experiments reported. Would you respond differently to reading the claims in this way than you would if you came across them in the manner outlined in question 2 above?
    Now, to give my honest answers as to how I reply to those questions:
    Question 1: I would not be inclined to accept the claims on the basis that they did not conform to my knowledge base.
    Question 2: my response would be very similar to my response to question 1, plus I would have doubts as to the honesty and reliability of the person/company making the claims. I would be highly suspicious of any test results shown.
    Question 3: I would take the claims a lot more seriously than I took the claims in the first 2 scenarios. I may not yet accept them but I would be inclined to give them a lot more credence and, if I did not accept them on the basis of the initial published account, I would accept them on evidence of the replication of the results by equally reputable researchers.
    Note that in all 3 cases we're talking about the same device and it is effective and does not violate any scientific principles. The only differences in the examples are the timing of the claims and the way in which they come to your attention. It is impossible to prove in scenarios 1 and 2 that the devices don't work because they actually do work. It is possible to give reasoned responses explaining why they can't possibly work that will convince many people that they don't, but that reasoning will be wrong and no-one really KNOWS that they don't work, they simply believe that they can't work and mistakenly accept that belief as knowledge.
    If these devices do work, we're currently in circumstances similar to those in my first 2 questions. Extreme scepticism is justified and the answers I gave above as my response to my first 2 questions are appropriate responses at those times and in those circumstances, given the level of my knowledge and the lack of published accounts from reputable sources.
    Correctly observing that there is no way currently known of producing a particular effect does not guarantee that it cannot be done.
    We are required to leave open the possibility that our current circumstances are those of my second scenario and that someone at some time in the future will publish an account that explains the effect to our satisfaction and the technique becomes accepted even though it is radically different to previous approaches as diffusion by the technique discovered by Schroeder radically differed from earlier diffusion techniques.
    Do I think this is going to happen here? No I don't, but at least I'm honest enough to admit that I would say exactly the same thing in response to my second scenario. I'm also old enough to know that in the past I have made judgements I considered absolutely correct on what at the time I considered was impeccable evidence, only to be later proven wrong. I'm also prepared to admit that I may do so again in the future. On something like these devices I'm prepared to be as sceptical as I can be but without actual direct evidence demonstrating how the claimed results were wrongly obtained, I'm not prepared to claim that I KNOW they are false and that they are impossible.
    David Aiken
    - Re: Ethan and MahlerFreak - MahlerFreak 21:26:12 03/11/07 (14)
      "As I pointed out, it is possible to obtain somewhat better absorption than 1 Sabin per square foot of device under some circumstances, including restricted bandwidth, from a passive device and without violating the Law of Conservation of Energy. We cannot say that there is no possible way of producing this kind of effect because we can never guarantee with 100% certainty that there isn't a way of passively producing the result."
      Wrong. What you pointed out is that panels have two sides, and so that doubles the surface area of the panel. You did not point out that panels can have more than 1 sabin per square foot, for the simple reason that they can't, without violating conservation of energy. Bad logic!
      "All I'm saying is that without direct evidence showing that the results were not genuinely obtained, there is a logical step involved in the move from the evidence of the plots to the conclusion that they are wrong. That step is inferential."
      Well, I don't have the benefits of a philosophy education, so I can't say what a valid inference is or not. All I can say is that some possibilities can be excluded without resort to experimentation. For instance, I can exclude the possibility of powering our electrical grid through perpetual motion machines - and perpetual motion is impossible for precisely the reasons that the results in question are impossible, namely conservation of energy.
      To your hypothetical questions, the answer is that of course I would be more likely to credit theories advanced by researchers with a track record. But your straw man is a logical non-sequiter: you are attempting to counter a quantitative argument with a sociological and psychological one. It is as though you were arguing that because at one time people were skeptical of ever building a practical aviation jet engine, we should now be prepared to reject calculations showing that you can't fly a 747 using a Briggs and Stratton lawn mower engine. The argument I made is a quantitative argument, which demonstrates that removing 97% percent of a room's broadband sound energy using passive devices representing 3% percent of the room's surface area violates conservation of energy. No amount of logic, philosophy, sociology, psychology, or random assertion will counter that argument - only an analysis which shows errors of very large quantitative significance in assumptions or calculations.
      And BTW, if you really want to counter the essentially Newtonian notion of conservation of energy, why not resort resort to relativity and quantum mechanics? For instance, the measured results are feasible if the devices in question uniformly transform the space in the room such that 97% of the sound energy is converted to matter. This is truly a Nobel prize winner, to say the very least. Of course, if this is the sort of possibility that you consider reasonable, it says more about your credulity than about the scientific credibility of these devices ...
      I have the same reaction as Ethan - why aren't the inventors of this device here defending their data, if only to throw enough BS to protect that significant segment of their potential market with big wallets and small understanding of science?
      - Re: Ethan and MahlerFreak - David Aiken 23:45:46 03/11/07 (13)
        
        In Reply to: Re: Ethan and MahlerFreak posted by MahlerFreak on March 11, 2007 at 21:26:12:
        
        You said: "To your hypothetical questions, the answer is that of course I would be more likely to credit theories advanced by researchers with a track record. But your straw man is a logical non-sequiter: you are attempting to counter a quantitative argument with a sociological and psychological one. It is as though you were arguing that because at one time people were skeptical of ever building a practical aviation jet engine, we should now be prepared to reject calculations showing that you can't fly a 747 using a Briggs and Stratton lawn mower engine. The argument I made is a quantitative argument, which demonstrates that removing 97% percent of a room's broadband sound energy using passive devices representing 3% percent of the room's surface area violates conservation of energy. No amount of logic, philosophy, sociology, psychology, or random assertion will counter that argument - only an analysis which shows errors of very large quantitative significance in assumptions or calculations."
        I haven't suggested anything like rejecting calculations that show you can't fly a 747 using a lawn mower engine. I haven't argued that you could remove 97% of the room's broadband surface energy using passive devices representing 3% of the room's surface area.
        I also haven't argued that these devices can produce the results shown in the waterfall plots.
        We don't have any acceptable or plausible evidence for what they can do. We have no evidence that they do absolutely nothing and if we claim they don't work, we're essentially saying that they either do nothing or do so little as to be of no value to the user. I'm saying that we need evidence to show that they either do nothing or do so little to be of no practical value before we say that they don't work. Nothing you or Ethan has said goes to that point.
        I don't dispute your reservations. I share them. I simply don't think they support the categorical 'don't work' pronouncement that Ethan made and which I originally responded to. I think we need something else apart from the points raised by both of you in reservation before we can make such a claim ourselves. We don't have proof that they don't work. We have good scientific reason for asserting that they don't do what they claim. That isn't the same thing.
        The point of the questions in my hypothetical scenarios was simply to show that we could be presented with claims about a product, even accurate claims about a product, and still be justified in holding strong doubts about the product because of the way in which the claims were presented and the state of our knowledge of acoustic technology at the time. We are justified in extreme scepticism in response to questions 1 and 2 in my view, and what we would want to see is test results showing what the product actually did. That's what we need here as well. Yes, there is a difference between this case and the case in my question 2, and that difference is that we know that Schroeder style diffusors work and, in question 2 I didn't suggest that any of the claims made for the diffusor exceeded what it could actually deliver. Even so, based on the amount of knowledge I indicated that you would have when you made your judgement in question 2, I think that all of us would probably have believed that accurate claims for what such a diffusor could deliver would have been unrealistic and implausible. We definitely believe the claims in this case to be unrealistic and implausible.
        If you say that you would have been sceptical about the claims in question 2 and you are sceptical about the claims here, but you know you can't be wrong here, then what difference between the scenario in question 2 and the circumstances in regard to the product we're discussing allow you to absolutely guarantee that you can't be wrong here? Let's allow that the claims being made by the manufacturer in this case are excessive and can't possibly be demonstrated. That still doesn't prove that the product doesn't work. If a manufacturer wants to claim that their speaker produces 250 dB output at 1 metre for 1 watt input using certain drivers and we know from the drivers specifications that such a output is impossible, does that prove that the speaker doesn't work? The speaker works if it only produces 80 dB at 1 metre for that input or even only 40 dB for that matter but it definitely doesn't work as claimed. How do you prove that the speaker actually doesn't work? You need tests which prove that it doesn't produce anything.
        We've got the equivalent of 250 dB claims and driver specs that demonstrate that nothing like 250 dB can be generated. We don't have evidence of what the thing does, so we don't know whether it fails to work at all, does so little as not to be of any practical value, or does something that would help but nothing at all like what was claimed. We aren't in a position to say they don't work.
        David Aiken
        
        Re: Ethan and MahlerFreak - Champion 01:11:48 03/12/07 (12)
        
        In Reply to: Re: Ethan and MahlerFreak posted by David Aiken on March 11, 2007 at 23:45:46:
        
        David, I don't think MF or Ethan has ever suggested that the device do nothing at all, just that it can't be that effective and it is highly unlikely that it will do anything significant with the size of the panel. I am sure putting anything in the room will has some effect acoustically, but whether it work as well as claimed is a different question.
        I don't have a degree in philosophy and I have little knowledge on acoustics comparing to any of you guys. But to me, if the manufacturer make a claim about the performance of a product that is almost impossible to achieve (with the current knowledge of science), and does not give a hint about how it can be done, then I have no reason to believe that it works. And how do you define 'work'? Well, to me, it 'works' if it perform as expected and meet the specifications. If it does not meet the specifications, then it does not work.
        Sure, strictly speaking, we cannot prove that the device does not work. Actually, we cannot prove anything wrong at all with 100% confidence. But if you go down that track then any discussion becomes meaningless. A manufacturer may claim that if you shine light on to his newly designed panel, then the sound will get absorbed whereever the reflect light reaches and 'publishes' the result. Can you proved that it is wrong without going to his lab and try it? I can't but I think it is his responsibility to prove that it is right. That is how science work. A claim is wrong if it violates the rules that we currently know of, until you can prove that it is right.
        
        An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious - David Aiken 14:58:33 03/12/07 (11)
        
        In Reply to: Re: Ethan and MahlerFreak posted by Champion on March 12, 2007 at 01:11:48:
        
        You may be right that neither has said they don't work. I've come to think that this thread has become more and more confused as it has proceeded, something I have to accept part of the responsibility for, and it has definitely run its term. I'm not even going to bother going back over it in order to confirm in detail what or wasn't said or by whom.
        I originally joined in simply to make one point. Ethan made a claim that they couldn't do what they claimed because you couldn't get those results with absorption. I wanted to make the point that proving something couldn't be done with absorption didn't mean it couldn't be done by some other means and that the devices claimed to use a different means.
        From there, Ethan and MahlerFreak started providing reasons why the difference between the before and after plots couldn't be obtained by any means. Those arguments are certainly compelling and I don't disagree with them, but I tended to obsess about my original point that proving that technique A doesn't work does not prove that technique B doesn't work, picking up on further statements they made which I felt were overly generalised and skimmed over genuine exceptions, plus responding to several misinterpretations of my position by them. I still wonder whether they actually believe I think these things can produce the results displayed by utilising some 'magic' method. I don't and never have. Anything they actually do has to be done by mechanisms that work according to the laws of physics.
        My only qualification to that point is that our understanding of those laws is currently imperfect, will remain so indefinitely, and that some of our advances in science make us realise that what we believed about one or more of those laws was wrong to some degree. I'm not suggesting that happens often or that it is the case here. I'm simply saying that we're not infallible and I don't like seeing statements made in terms I regard as too absolute, especially when they're made in the context of debunking something. It's one thing to point out the flaws in someone else's claims but I do think that when you do so, you should do your best to ensure that there aren't obvious logical flaws in your arguments. An invalid argument proves nothing and an invalid argument which attempts to show that something doesn't work or doesn't do what is claimed can actually weaken your position. I don't like seeing people who are saying things I am in broad agreement with doing what I regard as shooting themselves in the foot while doing so. I'd rather see them present a slightly more limited rebuttal that holds up against all objections.
        I don't agree with you that we can't prove anything at all with 100% confidence. We can definitely prove some things with 100% confidence. We can prove that aircraft do fly, or to put it more precisely, that flight in heavier than air vehicles is possible and we can prove that with 100% confidence. They're doing it and that's all the proof required. I don't think it's usually particularly difficult to prove that those things which do work actually do work. It's not too difficult, either, to prove that something that doesn't work actually doesn't work. Where things do get difficult is when we try to prove that a particular something absolutely can't work or doesn't exist or the like. Negatives are particularly hard to prove because testing doesn't go far enough on it's own. All a given test proves is that the thing didn't work under those conditions and that result can't be generalised to a can't work under any conditions conclusion. That's the original point I was attempting to make with Ethan back again. I am reluctant to believe that we can ever prove with 100% certainty that something won't work or doesn't exist, but we don't need an absolute 100% certainty for most things in life.
        While I do have a limited background in some science related areas, largely health related rather than 'hard science' like physics, my main tertiary qualification is in philosophy including a healthy dose of formal logic. That background does put a different spin on your understanding of the word "know" and what is entailed if you claim to know something. That is the basis of my original reservation and I was trying to make some of what is entailed a little clearer with my hypothetical scenario about Schroeder style diffusors but MahlerFreak simply missed the point there and regarded me as setting up a straw man. I wasn't. The point was that if you claim to know something that is subsequently proven wrong, then you really didn't know it. You held an extremely strong belief in it. I was trying to give an example of a situation in which a person would be tempted to say that they 'knew' something couldn't work but would subsequently would be proven wrong and to do so with something where neither Ethan or MahlerFreak would want to argue about the science involved, something where the only difference in the variations on the scenario was the amount of information you had in your possession when you had to make your judgement, and where the variations about the amount of knowledge you had were both plausible and relevant to the discussion in this thread. I think I came up with a good hypothetical but I don't seem to have made the point. I think there was just too much heat in the discussion by that stage.
        Anyway that's my take on the whole sorry saga and I think it's definitely best that we all draw it to an end at this point. I don't think any of us have presented our best points at various stages here, and we've all been a bit too eager to nitpick on detail and stray from a couple of genuine and quite serious points of principle by confusing measurable aspects relating to a given product and general principles about what sort of general claims can and can't be supported by certain sorts of evidence. As I said at the outset, I have to accept part of the responsibility for that, for which I apologise. I should probably try to keep my contributions here to the practical things, something Ethan and I rarely disagree on as many past threads in which we've both contributed, will show.
        David Aiken
        
        Re: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious - MahlerFreak 19:41:29 03/13/07 (5)
        
        In Reply to: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious posted by David Aiken on March 12, 2007 at 14:58:33:
        
        David,
        I've been out of town, helping my parents with a medical crisis, which largely explains both my lack of response the last two days and the free time I had in the previous days to engage in this discussion.
        I find significant parts of your last two posts to be inconsistent with your posts preceding - and I'm much more in agreement with the latest posts. In the spirit of your last post, it would be quite uncharitable, and unproductive, for me to be particular on this point.
        I certainly agree that progress is often made by those who choose to ignore the judgments of those who equate "impossible" with "improbable" or "beyond my imagination". My own career is sufficient evidence to prove this to me. At the same time, the concept of "impossible" is extremely useful even when it means "improbable to a very high degree of certainty". This explains why, although I certainly fit the profile of an audiophile - judged by my expenditures of passion, time, and money over 25 years of adult life - I am often despairing of the high-end audio industry overall.
        I was not joking about the perverse incentives underpinning high-end audio. Given the inherently subjective, psychoacoustical nature of listening to reproduced sound, the temptation to appeal to psychological factors is a powerful factor for any audio reproduction business. Given the superficially rational, scientific basis of the societies most able to afford high-end audio products, it is no surprise that high-end audio businesses will attempt to justify claims of significant subjective improvements through scientific theories and experiments - whether or not there is real science behind the product.
        And even when the science is real, the potential subjective impact is often greatly exaggerated - the real differences in physical sound pressure arriving at a listener's ears due to electronic and cable changes may be far less than moving the listener's head a couple of inches, for instance. (Note for fellow audiophiles - I did not say amplifiers and cables "sound the same". But: treating my ceiling with RPG diffusors, in conjunction with a number of other room treatments, created a very dramatic measurable and audible difference in sound, that I might describe as "tubes on steroids").
        So what? If the consumer is happy, who cares whether the happiness is due mostly to real or illusory differences? Well, you should. Real differences are more likely to matter to a broad range of consumers, while purely subjective difference are, by definition, personal. Any experienced high-end listener who's taken the time to do the comparison carefully recognizes that 128 kbps compressed audio does not have the same subjective quality of sound as CD (to say nothing of the high-resolution formats). But how will we marshal the credibility to convince the many millions of iTunes customers of this, when we are associated with an industry which systematically obfuscates and exaggerates both the scientific and subjective benefits of its products?
        The product we've been discussing is being marketed in exactly the worst possible way, from my perspective, in that it is represented as creating differences which are quantitatively impossible by universally accepted scientific principles, and furthermore undesirable even if they were true! And as I was careful to point out, the product may indeed "work", but not much better, and possibly much worse, than passive products of similar physical dimension.
        The high end audio industry often laments its failure to create broader based appeal. I would suggest that this failure is intrinsic to the industry as currently structured - much of it DEPENDS on the narrow appeal it has to listeners for whom subjective experience is substantially disconnected from physical reality. And yet, the best the industry has to offer is subjectively extraordinary to a very broad audience. By holding the industry to the highest scientific standards, we ultimately encourage the development of solutions of appeal to both perfectionists and "ordinary" consumers.
        And now it's time for me to terminate my participation in this discussion, and go listen to the Brahms 3rd, or Sibelius 6th, or Shostakovich 4th, or Mahler 7th, or any number of other works which I know will make me happy without resort to scientific analysis :)
        
        Re: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious - David Aiken 20:39:42 03/13/07 (4)
        
        In Reply to: Re: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious posted by MahlerFreak on March 13, 2007 at 19:41:29:
        
        "I find significant parts of your last two posts to be inconsistent with your posts preceding�"
        Well, the difference was that I started out with a point I wanted to make, then got progressively more distant from that point, before finally trying to get back to it at the end. I don't think I was inconsistent but I certainly got lost on some of the points, and ended up trying to prove the point I wanted to make from some things that weren't appropriate for that sort of proof. In other words, I ended up doing what I started criticising Ethan of doing and I ended up shooting myself in the foot on a couple of points as a result.
        Note: the following remarks ARE NOT related to acoustical or logical issues:
        You said "So what? If the consumer is happy, who cares whether the happiness is due mostly to real or illusory differences? Well, you should." and a bit later "The product we've been discussing is being marketed in exactly the worst possible way, from my perspective, in that it is represented as creating differences which are undesirable even if they were true!"
        I've got a slightly different take on these issues. I'm in this hobby for my own enjoyment and, as far as I'm concerned, what matters is whether something makes me happy. I am interested in whether something actually does something or not because there's no point in spending money on something that does nothing since something that does nothing can't add anything to my enjoyment. If the product does something, I'm less intereted from one perspective in whether it does what is claimed than I am in whether it enhances my listening enjoyment or not. That doesn't mean that I'm not interested in whether or not it does what is claimed or in how it produces the results it produces. I do have an interest in those things but those aspects of it don't affect my listening enjoyment, they're intellectual interests for me.
        I do think that knowing how something works is important. It much easier to improve something and/or make it more efficient if we know how it works. If I know how things work and what they actually do, it also makes it easier for me to shortlist products that may enhance my pleasure for audition when I'm thinking of making a change. Those aren't inconsequential benefits for me, or for anyone. In the end, however, after all of the looking/thinking about it/testing etc, I'm not going to buy something because I think it simply because it produces better results technically or it does the job more perfectly than the opposing products do. I'm going to make my purchase on the basis of what's going to give me more enjoyment when I listen to music. Some of what goes into making that judgement does relate to the performance measurements and some of it just boils down to my own personal taste. At the end of the day I want to be happy with the way my system sounds and, since I spend more time listening to my system than do others (after all, they have their own sytems too), I have no difficulty injecting a few personal factors into the decision process and acknowledging their contribution to my choice. If someone else disagrees with my choice, that's fine. They don't have to make the same choice for their system and I'd prefer they didn't. I get a lot of enjoyment from listening to friends' systems that do things differently to mine and which sound different to mine but, while I can find a lot of things to enjoy with those systems, I wouldn't necessarily like to live with them. I do want to be able to live with my system.
        So, I do agree with you that we do need to care about whether differences are real or illusory but I'm not overly worried if something produces a theoretically undesirable result and I happen to like that particular result. I'm quite happy to ackowledge that the product has some aspects usually considered undesirable if I buy it, because I'm prepared to acknowledge that my system isn't perfect and it does include compromises. The point is that where I compromise, I give up something that is less important to my enjoyment for something else which is more important to that enjoyment. I don't need to dress those choices up as something else, nor does anyone else have to do so when they make a different set of compromises. We all have our own individual tastes and tastes not only aren't logical, they don't have to be logical.
        David Aiken
        
        Re: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious - Ethan Winer 14:54:13 03/14/07 (3)
        
        In Reply to: Re: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious posted by David Aiken on March 13, 2007 at 20:39:42:
        
        Guys,
        I've been too busy to reply much lately either.
        > I am interested in whether something actually does something or not because there's no point in spending money on something that does nothing <
        Exactly.
        > I do think that knowing how something works is important. <
        Me too.
        So I assume we can now conclude that the panels in question probably do not really have the effect shown in the waterfall plots, yes?
        And by extension I assume we can further conclude that were there anything to those waterfall graphs, someone from the company would have chimed in by now to explain what we're overlooking.
        Hey, that works for me.
        --Ethan
        
        :-((((((((( - David Aiken 15:57:14 03/14/07 (2)
        
        In Reply to: Re: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious posted by Ethan Winer on March 14, 2007 at 14:54:13:
        
        "So I assume we can now conclude that the panels in question probably do not really have the effect shown in the waterfall plots, yes?"
        Well, we can assume that for those of us who participated in the thread. I wouldn't bet that everyone who didn't participate, including the many who didn't even see it, would agree with you.
        
        "And by extension I assume we can further conclude that were there anything to those waterfall graphs, someone from the company would have chimed in by now to explain what we're overlooking."
        No, we can't assume that. The company may be blissfully unaware of this whole thread.
        Stop being wicked! :-)
        David Aiken
        
        Re: :-((((((((( - Ethan Winer 10:54:02 03/15/07 (1)
        
        In Reply to: :-((((((((( posted by David Aiken on March 14, 2007 at 15:57:14:
        
        David,
        > The company may be blissfully unaware of this whole thread. <
        Unlikely given that the Robo guy in the Tweaks section saw this thread move to here. At least I assume that "Robo" is from that company. If you want to be sure they see it and have a chance to chime in, please invite them here. Personally, I'd love to hear their explanation.
        Really, David, I think this has gone about as far as it can. I use ETF all the time, and as I said much earlier in this thread, the Before and After graphs shown are unlike any ETF graphs I've ever seen.
        --Ethan
        
        Re: :-((((((((( - David Aiken 17:42:55 03/15/07 (0)
        
        In Reply to: Re: :-((((((((( posted by Ethan Winer on March 15, 2007 at 10:54:02:
        
        Ethan,
        How about I don't invite them.
        Given what we did to this thread without them here, I hate to think what we could do to a thread with them here.
        David Aiken
        
        Re: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious - LarryB 17:47:08 03/13/07 (3)
        
        In Reply to: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious posted by David Aiken on March 12, 2007 at 14:58:33:
        
        David's arguments are, in essence, an eloquent restatement of what is perhaps the most important lesson I learned in graduate school: "Absence of proof is not the same as proof of absence."
        By the way, I enjoyed this thread immensely. Seriously.
        Larry
        
        Re: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious - Ethan Winer 14:56:25 03/14/07 (0)
        
        In Reply to: Re: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious posted by LarryB on March 13, 2007 at 17:47:08:
        
        Larry,
        > "Absence of proof is not the same as proof of absence." <
        Great point, and that has ramifications far beyond audiophilia.
        But this does not mean that every conceivable crackpot theory deserves consideration solely because it cannot be proven false.
        --Ethan
        
        "Absence of proof is not�" states it a lot faster and better than I did. NT - David Aiken 19:58:07 03/13/07 (1)
        
        In Reply to: Re: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious posted by LarryB on March 13, 2007 at 17:47:08:
        
        It's a good thing I don't get paid by the word - LarryB 08:18:06 03/14/07 (0)
        
        In Reply to: "Absence of proof is not�" states it a lot faster and better than I did. NT posted by David Aiken on March 13, 2007 at 19:58:07:
        
        :) :)
        
        Re: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious - Champion 16:05:33 03/12/07 (0)
        
        In Reply to: An explanation/apology/conclusion to this thread? - caution: somewhat long but hopefully non-contentious posted by David Aiken on March 12, 2007 at 14:58:33:
        
        Hi David, I understand what you are trying to get at and it did make me think. I don't think you need to apologize. This is one of the very rare threads on AA that have gone this far and everyone is still saying things that make sense and do not just attack each other!!! And I am sure those who had follow the discussion actually learn alot, esp. with the detailed explanation from MF and Ethan.
        'something Ethan and I rarely disagree on as many past threads in which we've both contributed'
        I agree. And yes, you guys are great and that's why nowadays I tends to stick to this forum to learn rather than going to other forums on AA!!!

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